Information Display Regarding Playback Queue Subscriptions

ABSTRACT

Example techniques relate to playback queue subscriptions. An example implementation involves a computing system receiving, from a first computing device associated with a first user account, an instruction to enable subscription to a first playback queue associated with a first media playback system. In response to the instruction, the computing system enables second user accounts to subscribe to the first playback queue. The second user accounts are registered with respective second media playback systems in respective second household. The computing system receives, from a particular second media playback system, a request to subscribe to the first playback queue; and in response, sends one or more messages that update a control interface of the first control device to display a subscriber indication and (ii) sends one or more messages that populate a second playback queue of the particular second media playback system with audio tracks of the first playback queue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 120 to, and is acontinuation of, U.S. non-provisional patent application Ser. No.15/890,565, filed on Feb. 7, 2018, entitled “Information DisplayRegarding Playback Queue Subscriptions,” which is incorporated herein byreference in its entirety.

U.S. non-provisional patent application Ser. No. 15/890,565 claimspriority under 35 U.S.C. § 120 to, and is a continuation of, U.S.non-provisional patent application Ser. No. 14/674,384, filed on Mar.31, 2015, entitled “Information Display Regarding Playback QueueSubscriptions,” and issued as U.S. Pat. No. 9,891,880 on Feb. 13, 2018,which is incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The disclosure is related to consumer goods and, more particularly, tomethods, systems, products, features, services, and other elementsdirected to media playback or some aspect thereof.

BACKGROUND

Options for accessing and listening to digital audio in an out-loudsetting were limited until in 2003, when SONOS, Inc. filed for one ofits first patent applications, entitled “Method for Synchronizing AudioPlayback between Multiple Networked Devices,” and began offering a mediaplayback system for sale in 2005. The Sonos Wireless HiFi System enablespeople to experience music from many sources via one or more networkedplayback devices. Through a software control application installed on asmartphone, tablet, or computer, one can play what he or she wants inany room that has a networked playback device. Additionally, using thecontroller, for example, different songs can be streamed to each roomwith a playback device, rooms can be grouped together for synchronousplayback, or the same song can be heard in all rooms synchronously.

Given the ever growing interest in digital media, there continues to bea need to develop consumer-accessible technologies to further enhancethe listening experience.

BRIEF DESCRIPTION OF THE DRAWINGS

Features, aspects, and advantages of the presently disclosed technologymay be better understood with regard to the following description,appended claims, and accompanying drawings where:

FIG. 1 shows an example media playback system configuration in whichcertain embodiments may be practiced;

FIG. 2 shows a functional block diagram of an example playback device;

FIG. 3 shows a functional block diagram of an example control device;

FIG. 4 shows an example controller interface;

FIG. 5 shows a flow diagram for an example method;

FIG. 6A shows functions performed example playback devices and anexample control device;

FIG. 6B shows functions performed by an example control device;

FIG. 7 shows a flow diagram for an example method;

FIG. 8A shows functions performed by example playback systems and anexample control device;

FIG. 8B shows functions performed by an example control device;

FIG. 8C shows functions performed by an example control device;

FIG. 9 shows a flow diagram for an example method;

FIG. 10 shows functions performed by example playback systems and anexample control device;

FIG. 11A shows a flow diagram for an example method;

FIG. 11B shows a flow diagram for an example method; and

FIG. 12 shows functions performed by example playback systems and anexample control device.

The drawings are for the purpose of illustrating example embodiments,but it is understood that the inventions are not limited to thearrangements and instrumentality shown in the drawings.

DETAILED DESCRIPTION I. Overview

In various embodiments, a first playback device associated with a firstuser-account plays media content from a playback queue. Further, thefirst playback device may allow a second user-account to subscribe tothe playback queue so that a second playback device associated with thesecond user-account may play the media content contemporaneously withthe first playback device. In this context, it may be useful for acontrol device associated with the first user-account to provide anintuitive user interface for display of information regarding the seconduser-account's use of the playback queue.

The control device may be used to control operations of the firstplayback device and also display an indication that the seconduser-account is subscribing to the playback queue and/or that the secondplayback device is playing media content from the playback queue. Thisfacilitates a collaborative and interactive listening experience as wellas provides specific feedback to the first user-account as to whichuser-accounts are subscribing to the playback queue.

In some examples, the first playback device may allow multipleuser-accounts to subscribe to the playback queue. Here, the controldevice may also display an indicator of how many user-accounts aresubscribed to the playback queue. By monitoring trends in how manyuser-accounts are subscribing to the playback queue, it may be possibleto modify the contents of the playback queue to attract moreuser-accounts to subscribe to the playback queue.

Accordingly, some examples described herein involve, among other things,a control device configuring a first playback device associated with afirst user-account to (i) play media content from a playback queuecomprising one or more audio tracks stored at a network location and(ii) enable one or more other user-accounts associated with otherplayback devices to subscribe to the playback queue; the control devicereceiving a subscription indication that a second user-accountassociated with a second playback device has subscribed to the playbackqueue; and in response to receiving the subscription indication, thecontrol device displaying a subscriber indicator showing that the seconduser-account has subscribed to the playback queue. Other aspects of theexamples will be made apparent in the remainder of the descriptionherein.

In one aspect, an example non-transitory computer-readable medium storesinstructions that, when executed by a control device, cause the controldevice to perform functions. The functions comprise configuring a firstplayback device associated with a first user-account to (i) play mediacontent from a playback queue comprising one or more audio tracks storedat a network location and (ii) enable one or more other user-accountsassociated with other playback devices to subscribe to the playbackqueue. The functions further comprise receiving a subscriptionindication that a second user-account associated with a second playbackdevice has subscribed to the playback queue. The functions furthercomprise, in response to receiving the subscription indication,displaying a subscriber indicator on the control device showing that thesecond user-account has subscribed to the playback queue.

In yet another aspect, an example control device includes one or moreprocessors and a non-transitory computer-readable medium storinginstructions that, when executed by the one or more processors, causethe control device to perform functions. The functions compriseconfiguring a first playback device associated with a first user-accountto (i) play media content from a playback queue comprising one or moreaudio tracks stored at a network location and (ii) enable one or moreother user-accounts associated with other playback devices to subscribeto the playback queue. The functions further comprise receiving asubscription indication that a second user-account associated with asecond playback device has subscribed to the playback queue. Thefunctions further comprise, in response to receiving the subscriptionindication, displaying a subscriber indicator on the control deviceshowing that the second user-account has subscribed to the playbackqueue.

In yet another aspect, an example method performed by a control deviceincludes configuring a first playback device associated with a firstuser-account to (i) play media content from a playback queue comprisingone or more audio tracks stored at a network location and (ii) enableone or more other user-accounts associated with other playback devicesto subscribe to the playback queue. The method further comprisesreceiving a subscription indication that a second user-accountassociated with a second playback device has subscribed to the playbackqueue. The method further comprises, in response to receiving thesubscription indication, displaying a subscriber indicator on thecontrol device showing that the second user-account has subscribed tothe playback queue.

In yet another aspect, an example non-transitory computer-readablemedium stores instructions that, when executed by a control device,cause the control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The functions comprise receiving a notificationthat a second playback system associated with a second user-account isaccessing a first playback queue of the first group of playback devices.The first playback system and the control device are associated with afirst user-account. The functions further comprise displaying a firstindication that the second playback system is accessing the firstplayback queue. The functions further comprise receiving a command forthe second group of playback devices to access a second playback queueof a third playback system. The third playback system is associated witha third user-account. The functions further comprise, based on receivingthe command, configuring the second group of playback devices to accessthe second playback queue. The functions further comprise displaying asecond indication that the second group of playback devices is accessingthe second playback queue.

In yet another aspect, an example control device includes one or moreprocessors and a non-transitory computer-readable medium storinginstructions that, when executed by the one or more processors, causethe control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The functions comprise receiving a notificationthat a second playback system associated with a second user-account isaccessing a first playback queue of the first group of playback devices.The first playback system and the control device are associated with afirst user-account. The functions further comprise displaying a firstindication that the second playback system is accessing the firstplayback queue. The functions further comprise receiving a command forthe second group of playback devices to access a second playback queueof a third playback system. The third playback system is associated witha third user-account. The functions further comprise, based on receivingthe command, configuring the second group of playback devices to accessthe second playback queue. The functions further comprise displaying asecond indication that the second group of playback devices is accessingthe second playback queue.

In yet another aspect, an example method is performed by a controldevice configured to control a first playback system that comprises (i)a first group of one or more playback devices and (ii) a second group ofone or more playback devices. The method comprises receiving anotification that a second playback system associated with a seconduser-account is accessing a first playback queue of the first group ofplayback devices. The first playback system and the control device areassociated with a first user-account. The method further comprisesdisplaying a first indication that the second playback system isaccessing the first playback queue. The method further comprisesreceiving a command for the second group of playback devices to access asecond playback queue of a third playback system. The third playbacksystem is associated with a third user-account. The method furthercomprises, based on receiving the command, configuring the second groupof playback devices to access the second playback queue. The methodfurther comprises displaying a second indication that the second groupof playback devices is accessing the second playback queue.

In yet another aspect, an example non-transitory computer-readablemedium stores instructions that, when executed by a control device,cause the control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The functions comprise receiving a firstnotification that a second playback system associated with a seconduser-account is accessing a first playback queue of the first group ofplayback devices. The first playback system and the control device areassociated with a first user-account. The functions further comprisedisplaying a first indication that the second playback system isaccessing the first playback queue. The functions further comprisereceiving a second notification that a third playback system associatedwith a third user-account is accessing a second playback queue of thesecond group of playback devices. The functions further comprisedisplaying a second indication that the third playback system isaccessing the second playback queue.

In yet another aspect, an example control device includes one or moreprocessors and a non-transitory computer-readable medium storinginstructions that, when executed by the one or more processors, causethe control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The functions comprise receiving a firstnotification that a second playback system associated with a seconduser-account is accessing a first playback queue of the first group ofplayback devices. The first playback system and the control device areassociated with a first user-account. The functions further comprisedisplaying a first indication that the second playback system isaccessing the first playback queue. The functions further comprisereceiving a second notification that a third playback system associatedwith a third user-account is accessing a second playback queue of thesecond group of playback devices. The functions further comprisedisplaying a second indication that the third playback system isaccessing the second playback queue.

In yet another aspect, an example method is performed by a controldevice configured to control a first playback system that comprises (i)a first group of one or more playback devices and (ii) a second group ofone or more playback devices. The method comprises receiving a firstnotification that a second playback system associated with a seconduser-account is accessing a first playback queue of the first group ofplayback devices. The first playback system and the control device areassociated with a first user-account. The method further comprisesdisplaying a first indication that the second playback system isaccessing the first playback queue. The method further comprisesreceiving a second notification that a third playback system associatedwith a third user-account is accessing a second playback queue of thesecond group of playback devices. The method further comprisesdisplaying a second indication that the third playback system isaccessing the second playback queue.

In yet another aspect, an example non-transitory computer-readablemedium stores instructions that, when executed by a control device,cause the control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The first playback system and the control deviceare associated with a first user-account. The functions comprisereceiving a first command for the first group of playback devices toaccess a first playback queue of a second playback system. The secondplayback system is associated with a second user-account. The functionsfurther comprise, based on receiving the first command, configuring thefirst group of playback devices to access the first playback queue. Thefunctions further comprise displaying a first indication that the firstgroup of playback devices is accessing the first playback queue. Thefunctions further comprise receiving a second command for the secondgroup of playback devices to access a second playback queue of a thirdplayback system. The third playback system is associated with a thirduser-account. The functions further comprise, based on receiving thesecond command, configuring the second group of playback devices toaccess the second playback queue. The functions further comprisedisplaying a second indication that the second group of playback devicesis accessing the second playback queue.

In yet another aspect, an example control device includes one or moreprocessors and a non-transitory computer-readable medium storinginstructions that, when executed by the one or more processors, causethe control device to perform functions. The control device isconfigured to control a first playback system that comprises (i) a firstgroup of one or more playback devices and (ii) a second group of one ormore playback devices. The first playback system and the control deviceare associated with a first user-account. The functions comprisereceiving a first command for the first group of playback devices toaccess a first playback queue of a second playback system. The secondplayback system is associated with a second user-account. The functionsfurther comprise, based on receiving the first command, configuring thefirst group of playback devices to access the first playback queue. Thefunctions further comprise displaying a first indication that the firstgroup of playback devices is accessing the first playback queue. Thefunctions further comprise receiving a second command for the secondgroup of playback devices to access a second playback queue of a thirdplayback system. The third playback system is associated with a thirduser-account. The functions further comprise, based on receiving thesecond command, configuring the second group of playback devices toaccess the second playback queue. The functions further comprisedisplaying a second indication that the second group of playback devicesis accessing the second playback queue.

In yet another aspect, an example method is performed by a controldevice configured to control a first playback system that comprises (i)a first group of one or more playback devices and (ii) a second group ofone or more playback devices. The first playback system and the controldevice are associated with a first user-account. The method comprisesreceiving a first command for the first group of playback devices toaccess a first playback queue of a second playback system. The secondplayback system is associated with a second user-account. The methodfurther comprises, based on receiving the first command, configuring thefirst group of playback devices to access the first playback queue. Themethod further comprises displaying a first indication that the firstgroup of playback devices is accessing the first playback queue. Themethod further comprises receiving a second command for the second groupof playback devices to access a second playback queue of a thirdplayback system. The third playback system is associated with a thirduser-account. The method further comprises, based on receiving thesecond command, configuring the second group of playback devices toaccess the second playback queue. The method further comprisesdisplaying a second indication that the second group of playback devicesis accessing the second playback queue.

It will be understood by one of ordinary skill in the art that thisdisclosure includes numerous other embodiments. While some examplesdescribed herein may refer to functions performed by given actors suchas “users” and/or other entities, it should be understood that this isfor purposes of explanation only. The claims should not be interpretedto require action by any such example actor unless explicitly requiredby the language of the claims themselves.

II. Example Operating Environment

FIG. 1 shows an example configuration of a media playback system 100 inwhich one or more embodiments disclosed herein may be practiced orimplemented. The media playback system 100 as shown is associated withan example home environment having several rooms and spaces, such as forexample, a master bedroom, an office, a dining room, and a living room.As shown in the example of FIG. 1, the media playback system 100includes playback devices 102, 104, 106, 108, 110, 112, 114, 116, 118,120, 122, and 124, control devices 126 and 128, and a wired or wirelessnetwork router 130.

Further discussions relating to the different components of the examplemedia playback system 100 and how the different components may interactto provide a user with a media experience may be found in the followingsections. While discussions herein may generally refer to the examplemedia playback system 100, technologies described herein are not limitedto applications within, among other things, the home environment asshown in FIG. 1. For instance, the technologies described herein may beuseful in environments where multi-zone audio may be desired, such as,for example, a commercial setting like a restaurant, mall or airport, avehicle like a sports utility vehicle (SUV), bus or car, a ship or boat,an airplane, and so on.

a. Example Playback Devices

FIG. 2 shows a functional block diagram of an example playback device200 that may be configured to be one or more of the playback devices102-124 of the media playback system 100 of FIG. 1. The playback device200 may include a processor 202, software components 204, memory 206,audio processing components 208, audio amplifier(s) 210, speaker(s) 212,and a network interface 214 including wireless interface(s) 216 andwired interface(s) 218. In one case, the playback device 200 might notinclude the speaker(s) 212, but rather a speaker interface forconnecting the playback device 200 to external speakers. In anothercase, the playback device 200 may include neither the speaker(s) 212 northe audio amplifier(s) 210, but rather an audio interface for connectingthe playback device 200 to an external audio amplifier or audio-visualreceiver.

In one example, the processor 202 may be a clock-driven computingcomponent configured to process input data according to instructionsstored in the memory 206. The memory 206 may be a tangiblecomputer-readable medium configured to store instructions executable bythe processor 202. For instance, the memory 206 may be data storage thatcan be loaded with one or more of the software components 204 executableby the processor 202 to achieve certain functions. In one example, thefunctions may involve the playback device 200 retrieving audio data froman audio source or another playback device. In another example, thefunctions may involve the playback device 200 sending audio data toanother device or playback device on a network. In yet another example,the functions may involve pairing of the playback device 200 with one ormore playback devices to create a multi-channel audio environment.

Certain functions may involve the playback device 200 synchronizingplayback of audio content with one or more other playback devices.During synchronous playback, a listener will preferably not be able toperceive time-delay differences between playback of the audio content bythe playback device 200 and the one or more other playback devices. U.S.Pat. No. 8,234,395 entitled, “System and method for synchronizingoperations among a plurality of independently clocked digital dataprocessing devices,” which is hereby incorporated by reference, providesin more detail some examples for audio playback synchronization amongplayback devices.

The memory 206 may further be configured to store data associated withthe playback device 200, such as one or more zones and/or zone groupsthe playback device 200 is a part of, audio sources accessible by theplayback device 200, or a playback queue that the playback device 200(or some other playback device) may be associated with. The data may bestored as one or more state variables that are periodically updated andused to describe the state of the playback device 200. The memory 206may also include the data associated with the state of the other devicesof the media system, and shared from time to time among the devices sothat one or more of the devices have the most recent data associatedwith the system. Other embodiments are also possible.

The audio processing components 208 may include one or moredigital-to-analog converters (DAC), an audio preprocessing component, anaudio enhancement component or a digital signal processor (DSP), and soon. In one embodiment, one or more of the audio processing components208 may be a subcomponent of the processor 202. In one example, audiocontent may be processed and/or intentionally altered by the audioprocessing components 208 to produce audio signals. The produced audiosignals may then be provided to the audio amplifier(s) 210 foramplification and playback through speaker(s) 212. Particularly, theaudio amplifier(s) 210 may include devices configured to amplify audiosignals to a level for driving one or more of the speakers 212. Thespeaker(s) 212 may include an individual transducer (e.g., a “driver”)or a complete speaker system involving an enclosure with one or moredrivers. A particular driver of the speaker(s) 212 may include, forexample, a subwoofer (e.g., for low frequencies), a mid-range driver(e.g., for middle frequencies), and/or a tweeter (e.g., for highfrequencies). In some cases, each transducer in the one or more speakers212 may be driven by an individual corresponding audio amplifier of theaudio amplifier(s) 210. In addition to producing analog signals forplayback by the playback device 200, the audio processing components 208may be configured to process audio content to be sent to one or moreother playback devices for playback.

Audio content to be processed and/or played back by the playback device200 may be received from an external source, such as via an audioline-in input connection (e.g., an auto-detecting 3.5 mm audio line-inconnection) or the network interface 214.

The microphone(s) 220 may include an audio sensor configured to convertdetected sounds into electrical signals. The electrical signal may beprocessed by the audio processing components 208 and/or the processor202. The microphone(s) 220 may be positioned in one or more orientationsat one or more locations on the playback device 200. The microphone(s)220 may be configured to detect sound within one or more frequencyranges. In one case, one or more of the microphone(s) 220 may beconfigured to detect sound within a frequency range of audio that theplayback device 200 is capable or rendering. In another case, one ormore of the microphone(s) 220 may be configured to detect sound within afrequency range audible to humans. Other examples are also possible.

The network interface 214 may be configured to facilitate a data flowbetween the playback device 200 and one or more other devices on a datanetwork. As such, the playback device 200 may be configured to receiveaudio content over the data network from one or more other playbackdevices in communication with the playback device 200, network deviceswithin a local area network, or audio content sources over a wide areanetwork such as the Internet. In one example, the audio content andother signals transmitted and received by the playback device 200 may betransmitted in the form of digital packet data containing an InternetProtocol (IP)-based source address and IP-based destination addresses.In such a case, the network interface 214 may be configured to parse thedigital packet data such that the data destined for the playback device200 is properly received and processed by the playback device 200.

As shown, the network interface 214 may include wireless interface(s)216 and wired interface(s) 218. The wireless interface(s) 216 mayprovide network interface functions for the playback device 200 towirelessly communicate with other devices (e.g., other playbackdevice(s), speaker(s), receiver(s), network device(s), control device(s)within a data network the playback device 200 is associated with) inaccordance with a communication protocol (e.g., any wireless standardincluding IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.15, 4Gmobile communication standard, and so on). The wired interface(s) 218may provide network interface functions for the playback device 200 tocommunicate over a wired connection with other devices in accordancewith a communication protocol (e.g., IEEE 802.3). While the networkinterface 214 shown in FIG. 2 includes both wireless interface(s) 216and wired interface(s) 218, the network interface 214 may in someembodiments include only wireless interface(s) or only wiredinterface(s).

In one example, the playback device 200 and one other playback devicemay be paired to play two separate audio components of audio content.For instance, playback device 200 may be configured to play a leftchannel audio component, while the other playback device may beconfigured to play a right channel audio component, thereby producing orenhancing a stereo effect of the audio content. The paired playbackdevices (also referred to as “bonded playback devices”) may further playaudio content in synchrony with other playback devices.

In another example, the playback device 200 may be sonicallyconsolidated with one or more other playback devices to form a single,consolidated playback device. A consolidated playback device may beconfigured to process and reproduce sound differently than anunconsolidated playback device or playback devices that are paired,because a consolidated playback device may have additional speakerdrivers through which audio content may be rendered. For instance, ifthe playback device 200 is a playback device designed to render lowfrequency range audio content (i.e. a subwoofer), the playback device200 may be consolidated with a playback device designed to render fullfrequency range audio content. In such a case, the full frequency rangeplayback device, when consolidated with the low frequency playbackdevice 200, may be configured to render only the mid and high frequencycomponents of audio content, while the low frequency range playbackdevice 200 renders the low frequency component of the audio content. Theconsolidated playback device may further be paired with a singleplayback device or yet another consolidated playback device.

By way of illustration, SONOS, Inc. presently offers (or has offered)for sale certain playback devices including a “PLAY:1,” “PLAY:3,”“PLAY:5,” “PLAYBAR,” “CONNECT:AMP,” “CONNECT,” and “SUB.” Any otherpast, present, and/or future playback devices may additionally oralternatively be used to implement the playback devices of exampleembodiments disclosed herein. Additionally, it is understood that aplayback device is not limited to the example illustrated in FIG. 2 orto the SONOS product offerings. For example, a playback device mayinclude a wired or wireless headphone. In another example, a playbackdevice may include or interact with a docking station for personalmobile media playback devices. In yet another example, a playback devicemay be integral to another device or component such as a television, alighting fixture, or some other device for indoor or outdoor use.

b. Example Playback Zone Configurations

Referring back to the media playback system 100 of FIG. 1, theenvironment may have one or more playback zones, each with one or moreplayback devices. The media playback system 100 may be established withone or more playback zones, after which one or more zones may be added,or removed to arrive at the example configuration shown in FIG. 1. Eachzone may be given a name according to a different room or space such asan office, bathroom, master bedroom, bedroom, kitchen, dining room,living room, and/or balcony. In one case, a single playback zone mayinclude multiple rooms or spaces. In another case, a single room orspace may include multiple playback zones.

As shown in FIG. 1, the balcony, dining room, kitchen, bathroom, office,and bedroom zones each have one playback device, while the living roomand master bedroom zones each have multiple playback devices. In theliving room zone, playback devices 104, 106, 108, and 110 may beconfigured to play audio content in synchrony as individual playbackdevices, as one or more bonded playback devices, as one or moreconsolidated playback devices, or any combination thereof. Similarly, inthe case of the master bedroom, playback devices 122 and 124 may beconfigured to play audio content in synchrony as individual playbackdevices, as a bonded playback device, or as a consolidated playbackdevice.

In one example, one or more playback zones in the environment of FIG. 1may each be playing different audio content. For instance, the user maybe grilling in the balcony zone and listening to hip hop music beingplayed by the playback device 102 while another user may be preparingfood in the kitchen zone and listening to classical music being playedby the playback device 114. In another example, a playback zone may playthe same audio content in synchrony with another playback zone. Forinstance, the user may be in the office zone where the playback device118 is playing the same rock music that is being played by playbackdevice 102 in the balcony zone. In such a case, playback devices 102 and118 may be playing the rock music in synchrony such that the user mayseamlessly (or at least substantially seamlessly) enjoy the audiocontent that is being played out-loud while moving between differentplayback zones. Synchronization among playback zones may be achieved ina manner similar to that of synchronization among playback devices, asdescribed in previously referenced U.S. Pat. No. 8,234,395.

As suggested above, the zone configurations of the media playback system100 may be dynamically modified, and in some embodiments, the mediaplayback system 100 supports numerous configurations. For instance, if auser physically moves one or more playback devices to or from a zone,the media playback system 100 may be reconfigured to accommodate thechange(s). For instance, if the user physically moves the playbackdevice 102 from the balcony zone to the office zone, the office zone maynow include both the playback device 118 and the playback device 102.The playback device 102 may be paired or grouped with the office zoneand/or renamed if so desired via a control device such as the controldevices 126 and 128. On the other hand, if the one or more playbackdevices are moved to a particular area in the home environment that isnot already a playback zone, a new playback zone may be created for theparticular area.

Further, different playback zones of the media playback system 100 maybe dynamically combined into zone groups or split up into individualplayback zones. For instance, the dining room zone and the kitchen zone114 may be combined into a zone group for a dinner party such thatplayback devices 112 and 114 may render audio content in synchrony. Onthe other hand, the living room zone may be split into a television zoneincluding playback device 104, and a listening zone including playbackdevices 106, 108, and 110, if the user wishes to listen to music in theliving room space while another user wishes to watch television.

c. Example Control Devices

FIG. 3 shows a functional block diagram of an example control device 300that may be configured to be one or both of the control devices 126 and128 of the media playback system 100. As shown, the control device 300may include a processor 302, memory 304, a network interface 306, and auser interface 308. In one example, the control device 300 may be adedicated controller for the media playback system 100. In anotherexample, the control device 300 may be a network device on which mediaplayback system controller application software may be installed, suchas for example, an iPhone™ iPad™ or any other smart phone, tablet ornetwork device (e.g., a networked computer such as a PC or Mac™).

The processor 302 may be configured to perform functions relevant tofacilitating user access, control, and configuration of the mediaplayback system 100. The memory 304 may be configured to storeinstructions executable by the processor 302 to perform those functions.The memory 304 may also be configured to store the media playback systemcontroller application software and other data associated with the mediaplayback system 100 and the user.

The microphone(s) 310 may include an audio sensor configured to convertdetected sounds into electrical signals. The electrical signal may beprocessed by the processor 302. In one case, if the control device 300is a device that may also be used as a means for voice communication orvoice recording, one or more of the microphone(s) 310 may be amicrophone for facilitating those functions. For instance, the one ormore of the microphone(s) 310 may be configured to detect sound within afrequency range that a human is capable of producing and/or a frequencyrange audible to humans. Other examples are also possible.

In one example, the network interface 306 may be based on an industrystandard (e.g., infrared, radio, wired standards including IEEE 802.3,wireless standards including IEEE 802.11a, 802.11b, 802.11g, 802.11n,802.11ac, 802.15, 4G mobile communication standard, and so on). Thenetwork interface 306 may provide a means for the control device 300 tocommunicate with other devices in the media playback system 100. In oneexample, data and information (e.g., such as a state variable) may becommunicated between control device 300 and other devices via thenetwork interface 306. For instance, playback zone and zone groupconfigurations in the media playback system 100 may be received by thecontrol device 300 from a playback device or another network device, ortransmitted by the control device 300 to another playback device ornetwork device via the network interface 306. In some cases, the othernetwork device may be another control device.

Playback device control commands such as volume control and audioplayback control may also be communicated from the control device 300 toa playback device via the network interface 306. As suggested above,changes to configurations of the media playback system 100 may also beperformed by a user using the control device 300. The configurationchanges may include adding/removing one or more playback devices to/froma zone, adding/removing one or more zones to/from a zone group, forminga bonded or consolidated player, separating one or more playback devicesfrom a bonded or consolidated player, among others. Accordingly, thecontrol device 300 may sometimes be referred to as a controller, whetherthe control device 300 is a dedicated controller or a network device onwhich media playback system controller application software isinstalled.

The user interface 308 of the control device 300 may be configured tofacilitate user access and control of the media playback system 100, byproviding a controller interface such as the controller interface 400shown in FIG. 4. The controller interface 400 includes a playbackcontrol region 410, a playback zone region 420, a playback status region430, a playback queue region 440, and an audio content sources region450. The user interface 400 as shown is just one example of a userinterface that may be provided on a network device such as the controldevice 300 of FIG. 3 (and/or the control devices 126 and 128 of FIG. 1)and accessed by users to control a media playback system such as themedia playback system 100. Other user interfaces of varying formats,styles, and interactive sequences may alternatively be implemented onone or more network devices to provide comparable control access to amedia playback system.

The playback control region 410 may include selectable (e.g., by way oftouch or by using a cursor) icons to cause playback devices in aselected playback zone or zone group to play or pause, fast forward,rewind, skip to next, skip to previous, enter/exit shuffle mode,enter/exit repeat mode, enter/exit cross fade mode. The playback controlregion 410 may also include selectable icons to modify equalizationsettings, and playback volume, among other possibilities.

The playback zone region 420 may include representations of playbackzones within the media playback system 100. In some embodiments, thegraphical representations of playback zones may be selectable to bringup additional selectable icons to manage or configure the playback zonesin the media playback system, such as a creation of bonded zones,creation of zone groups, separation of zone groups, and renaming of zonegroups, among other possibilities.

For example, as shown, a “group” icon may be provided within each of thegraphical representations of playback zones. The “group” icon providedwithin a graphical representation of a particular zone may be selectableto bring up options to select one or more other zones in the mediaplayback system to be grouped with the particular zone. Once grouped,playback devices in the zones that have been grouped with the particularzone will be configured to play audio content in synchrony with theplayback device(s) in the particular zone. Analogously, a “group” iconmay be provided within a graphical representation of a zone group. Inthis case, the “group” icon may be selectable to bring up options todeselect one or more zones in the zone group to be removed from the zonegroup. Other interactions and implementations for grouping andungrouping zones via a user interface such as the user interface 400 arealso possible. The representations of playback zones in the playbackzone region 420 may be dynamically updated as playback zone or zonegroup configurations are modified.

The playback status region 430 may include graphical representations ofaudio content that is presently being played, previously played, orscheduled to play next in the selected playback zone or zone group. Theselected playback zone or zone group may be visually distinguished onthe user interface, such as within the playback zone region 420 and/orthe playback status region 430. The graphical representations mayinclude track title, artist name, album name, album year, track length,and other relevant information that may be useful for the user to knowwhen controlling the media playback system via the user interface 400.

The playback queue region 440 may include graphical representations ofaudio content in a playback queue associated with the selected playbackzone or zone group. In some embodiments, each playback zone or zonegroup may be associated with a playback queue containing informationcorresponding to zero or more audio items for playback by the playbackzone or zone group. For instance, each audio item in the playback queuemay comprise a uniform resource identifier (URI), a uniform resourcelocator (URL) or some other identifier that may be used by a playbackdevice in the playback zone or zone group to find and/or retrieve theaudio item from a local audio content source or a networked audiocontent source, possibly for playback by the playback device.

In one example, a playlist may be added to a playback queue, in whichcase information corresponding to each audio item in the playlist may beadded to the playback queue. In another example, audio items in aplayback queue may be saved as a playlist. In a further example, aplayback queue may be empty, or populated but “not in use” when theplayback zone or zone group is playing continuously streaming audiocontent, such as Internet radio that may continue to play untilotherwise stopped, rather than discrete audio items that have playbackdurations. In an alternative embodiment, a playback queue can includeInternet radio and/or other streaming audio content items and be “inuse” when the playback zone or zone group is playing those items. Otherexamples are also possible.

When playback zones or zone groups are “grouped” or “ungrouped,”playback queues associated with the affected playback zones or zonegroups may be cleared or re-associated. For example, if a first playbackzone including a first playback queue is grouped with a second playbackzone including a second playback queue, the established zone group mayhave an associated playback queue that is initially empty, that containsaudio items from the first playback queue (such as if the secondplayback zone was added to the first playback zone), that contains audioitems from the second playback queue (such as if the first playback zonewas added to the second playback zone), or a combination of audio itemsfrom both the first and second playback queues. Subsequently, if theestablished zone group is ungrouped, the resulting first playback zonemay be re-associated with the previous first playback queue, or beassociated with a new playback queue that is empty or contains audioitems from the playback queue associated with the established zone groupbefore the established zone group was ungrouped. Similarly, theresulting second playback zone may be re-associated with the previoussecond playback queue, or be associated with a new playback queue thatis empty, or contains audio items from the playback queue associatedwith the established zone group before the established zone group wasungrouped. Other examples are also possible.

Referring back to the user interface 400 of FIG. 4, the graphicalrepresentations of audio content in the playback queue region 440 mayinclude track titles, artist names, track lengths, and other relevantinformation associated with the audio content in the playback queue. Inone example, graphical representations of audio content may beselectable to bring up additional selectable icons to manage and/ormanipulate the playback queue and/or audio content represented in theplayback queue. For instance, a represented audio content may be removedfrom the playback queue, moved to a different position within theplayback queue, or selected to be played immediately, or after anycurrently playing audio content, among other possibilities. A playbackqueue associated with a playback zone or zone group may be stored in amemory on one or more playback devices in the playback zone or zonegroup, on a playback device that is not in the playback zone or zonegroup, and/or some other designated device.

The audio content sources region 450 may include graphicalrepresentations of selectable audio content sources from which audiocontent may be retrieved and played by the selected playback zone orzone group. Discussions pertaining to audio content sources may be foundin the following section.

d. Example Audio Content Sources

As indicated previously, one or more playback devices in a zone or zonegroup may be configured to retrieve for playback audio content (e.g.according to a corresponding URI or URL for the audio content) from avariety of available audio content sources. In one example, audiocontent may be retrieved by a playback device directly from acorresponding audio content source (e.g., a line-in connection). Inanother example, audio content may be provided to a playback device overa network via one or more other playback devices or network devices.

Example audio content sources may include a memory of one or moreplayback devices in a media playback system such as the media playbacksystem 100 of FIG. 1, local music libraries on one or more networkdevices (such as a control device, a network-enabled personal computer,or a networked-attached storage (NAS), for example), streaming audioservices providing audio content via the Internet (e.g., the cloud), oraudio sources connected to the media playback system via a line-in inputconnection on a playback device or network devise, among otherpossibilities.

In some embodiments, audio content sources may be regularly added orremoved from a media playback system such as the media playback system100 of FIG. 1. In one example, an indexing of audio items may beperformed whenever one or more audio content sources are added, removedor updated. Indexing of audio items may involve scanning foridentifiable audio items in all folders/directory shared over a networkaccessible by playback devices in the media playback system, andgenerating or updating an audio content database containing metadata(e.g., title, artist, album, track length, among others) and otherassociated information, such as a URI or URL for each identifiable audioitem found. Other examples for managing and maintaining audio contentsources may also be possible.

The above discussions relating to playback devices, controller devices,playback zone configurations, and media content sources provide onlysome examples of operating environments within which functions andmethods described below may be implemented. Other operating environmentsand configurations of media playback systems, playback devices, andnetwork devices not explicitly described herein may also be applicableand suitable for implementation of the functions and methods.

III. Example Methods Related to Information Display Regarding PlaybackQueue Subscriptions

As discussed above, some examples described herein involve, among otherthings, a control device configuring a first playback device associatedwith a first user-account to (i) play media content from a playbackqueue comprising one or more audio tracks stored at a network locationand (ii) enable one or more other user-accounts associated with otherplayback devices to subscribe to the playback queue; the control devicereceiving a subscription indication that a second user-accountassociated with a second playback device has subscribed to the playbackqueue; and in response to receiving the subscription indication, thecontrol device displaying a subscriber indicator showing that the seconduser-account has subscribed to the playback queue. Other aspects of theexamples will be made apparent in the remainder of the descriptionherein.

Methods 500, 700, 900, and 1100 respectively shown in FIGS. 5, 7, 9,11A, and 11B present example methods that can be implemented within anoperating environment involving, for example, one or more of the mediaplayback system 100 of FIG. 1, one or more of the playback device 200 ofFIG. 2, and one or more of the control device 300 of FIG. 3. Methods500, 700, 900, and 1100 may include one or more operations, functions,or actions as illustrated by one or more of blocks 502, 504, 506, 702,704, 706, 708, 710, 902, 904, 906, 908, 1102, 1104, 1106, 1108, 1110,and 1112. Although the blocks are illustrated in sequential order, theseblocks may also be performed in parallel, and/or in a different orderthan those described herein. Also, the various blocks may be combinedinto fewer blocks, divided into additional blocks, and/or removed basedupon the desired implementation.

In addition, for the methods 500, 700, 900, and 1100, and otherprocesses and methods disclosed herein, the flowcharts showfunctionality and operation of one possible implementation of presentembodiments. In this regard, each block may represent a module, asegment, or a portion of program code, which includes one or moreinstructions executable by a processor for implementing specific logicalfunctions or steps in the process. The program code may be stored on anytype of computer-readable medium, for example, such as a storage deviceincluding a disk or hard drive. The computer-readable medium may includenon-transitory computer-readable medium, for example, such ascomputer-readable media that stores data for short periods of time likeregister memory, processor cache, and Random Access Memory (RAM). Thecomputer-readable medium may also include non-transitory media, such assecondary or persistent long-term storage, like read-only memory (ROM),optical or magnetic disks, compact-disc read-only memory (CD-ROM), forexample. The computer-readable media may also be any other volatile ornon-volatile storage systems. The computer-readable medium may beconsidered a computer-readable storage medium, for example, or atangible storage device. In addition, for the methods 500, 700, 900, and1100 and other processes and methods disclosed herein, each block inFIGS. 5, 7, 9, 11A, and 11B may represent circuitry that is wired toperform the specific logical functions in the process.

At block 502, the method 500 includes configuring a first playbackdevice associated with a first user-account to (i) play media contentfrom a playback queue comprising one or more audio tracks stored at anetwork location and (ii) enable one or more other user-accountsassociated with other playback devices to subscribe to the playbackqueue.

Referring to FIG. 6A as an example, the control device 602 may beconfigured to control a “living room” playback zone that includes theplayback device 604. The control device 602 and the playback device 604are associated with the user-account A, the playback device 608 isassociated with the user-account B, the playback device 610 isassociated with the user-account C, and the playback device 612 isassociated with the user-account D.

The control device 602 may send a command 620 to the playback device604, configuring the playback device 604 to (i) play media content fromthe playback queue 606 and (ii) enable user-accounts B, C, and D tosubscribe to the playback queue 606, thereby allowing the playbackdevices 608, 610, and 612 to access the playback queue 606. In someexamples, the command 620 may cause the playback device 604 to make theplayback queue 606 publically available to any user-account, not justuser-accounts specified by the command 620.

In some examples, the playback queue 606 is stored at the playbackdevice 604, but in other examples the playback queue 606 is stored atanother playback device or at a server (not shown). In some embodiments,the server is associated with the user-accounts A, B, C, and D. Theplayback queue 606 may include uniform resource locators (URLs), uniformresource identifiers (URIs), or any other data identifying respectivenetwork locations for one or more audio tracks. In other examples, theplayback queue 606 includes the one or more audio tracks themselves.Accordingly, the playback device 604 (individually or in combinationwith control device 602) may provide, to the playback devices 608, 610,and 612, a network location of the playback queue 606. Alternatively, ifthe playback queue 606 is located at the playback device 604, theplayback device 604 may allow the playback devices 608, 610, and 612 toaccess the playback queue 606 at the playback device 604.

At block 504, the method 500 includes receiving a subscriptionindication that a second user-account associated with a second playbackdevice has subscribed to the playback queue. For example, the controldevice 602 may receive subscription indication 628 from the playbackdevice 608 which indicates that the user-account B has subscribed to theplayback queue 606. The subscription indication 628 may specificallyidentify the user-account B, the playback device 608, and/or theplayback queue 606. In other examples, the subscription indication maybe received from the playback device 604 in response to the playbackdevice 604 receiving an indication from the playback device 608 that theuser-account B has subscribed to the playback queue 606. The controldevice 602 may receive the subscription indication from other devices aswell. For example, the control device 602 may receive the subscriptionindication from a server configured to communicate status informationregarding playback queue subscriptions between different playbackdevices and/or different user-accounts.

At block 506, the method 500 includes, in response to receiving thesubscription indication, displaying a subscriber indicator on thecontrol device showing that the second user-account has subscribed tothe playback queue. For example, the control device 602 may display thesubscriber indicator 640 which indicates that the user-account B hassubscribed to the playback queue 606. The subscriber indicator 640 maybe a pictorial representation recognizable to a user of control device602 as corresponding to the user-account B, or an avatar or a photo of auser associated with user-account B. The subscriber indicator 640 mayappear in a first state—represented by a solid line in FIG.6A—indicating that the user-account B is subscribed to the playbackqueue 606 and is currently accessing the playback queue 606 for playbackof media content.

The method 500 may further include displaying a global indicator thatindicates a quantity of user-accounts that are subscribed to theplayback queue. For example, the control device 602 may display theglobal indicator 630, which indicates that there are threeuser-accounts, namely user-accounts B, C, and D that are subscribed tothe playback queue 606. In this example, user-accounts B, C, and D aresubscribed to the playback queue 606 but might or might not be currentlyaccessing the playback queue 606 to play audio content. Morespecifically, the global indicator 630 may show a total number ofuser-accounts that are subscribed to the playback queue 606, whether ornot the subscribed user-accounts are actually accessing the playbackqueue 606.

The method 500 may further include displaying an active accountindicator that indicates a quantity of user-accounts that are subscribedto the playback queue and are currently accessing an audio track of theplayback queue for playback. For example, the active account indicator632 indicates that there are two user-accounts, namely user-accounts Band D that are subscribed to the playback queue 606 and are currentlyaccessing an audio track of the playback queue 606 for playback. Forexample, even though the user-account C is subscribed to the playbackqueue 606, the user-account C might not be accessing the playback queue606 for playback of audio content. As a result, the active accountindicator 632 indicates that only two user accounts (B and D) arecurrently accessing the playback queue 606.

Generally, the global indicator and the active account indicator may bepresented in any manner that indicates, explicitly or implicitly, (i)the quantity of user-accounts that are subscribed to the playback queueand (ii) the quantity of user-accounts that are accessing an audio trackof the playback queue. In some embodiments, the global indicator and theactive account indicator may together explicitly indicate (i) thequantity of user-accounts that are subscribed to the playback queue and(ii) the quantity of user-accounts that are subscribed to the playbackqueue 606 and are not currently accessing an audio track of the playbackqueue 606. In other embodiments, the global indicator and the activeaccount indicator may together explicitly indicate (i) the quantity ofuser-accounts that are subscribed to the playback queue and are notcurrently accessing an audio track of the playback queue 606 and (ii)the quantity of user-accounts that are subscribed to the playback queueand are currently accessing an audio track of the playback queue 606.

The method 500 may further include receiving a command to play aparticular audio track from the playback queue; and in response toreceiving the command, configuring the first playback device to play theparticular audio track. In this context, playback of the particularaudio track by the first playback device may cause the second playbackdevice to also play the particular audio track at the substantially sametime as the first playback device.

For example, the control device 602 may receive the command via a userinterface such as a touchscreen. In some examples, the user interfacemay resemble controller interface 400 of FIG. 4. The command may be a“play current track” command, a “play next track” command, a “playprevious track” command, or may be a command to play a specific audiotrack listed in the playback queue section 440, for example. In responseto receiving the command, the control device 602 may control theplayback device 604 to play track 607 of the playback queue 606, forexample. In some embodiments this causes the playback device 604 tocoordinate with the playback device 608 so that the playback device 608plays the track 607 at substantially the same time as the playbackdevice 604. For example, the playback device 604 (or an intermediaryserver) may provide, to the playback device 608, timing information forplayback of the track 607 that the playback device 608 will then use toplay back track 607 at substantially the same time as playback device604.

In some embodiments, the playback devices 604 and 608 may be located indifferent locations that are sufficiently far from each other such thata person who hears audio from playback device 604 cannot hear audio fromplayback device 608, and vice versa. For example, the playback device604 may be included in a first playback system comprising one or moreplayback devices in a first household and the playback device 608 may beincluded in a second playback system comprising one or more playbackdevices in a second household. In such a scenario, it is not necessaryfor the playback devices 604 and 608 to play audio in synchrony in thesame manner that two playback devices in the same location might playaudio content in synchrony as described previously herein. Therefore, insome embodiments, playback devices 604 and 608 may play audio track 607at substantially the same time, but perhaps not necessarily in synchronyas described herein. However, in other embodiments the playback devices604 and 608 may play audio track 607 in synchrony as described herein,even though such tightly-coordinated synchronous playback may not berequired in all situations.

Referring to FIG. 6B as an example, the control device 602 is shownoperating in a subscription management mode. The control device 602 isshown displaying a subscriber region 652 and an additional user-accountsregion 654 within a touchscreen. Subscriber indicators 640 and 642 aredisplayed within the subscriber region 652, indicating that theuser-accounts B and C are currently enabled to subscribe to the playbackqueue 606. The subscriber indicator 644 is displayed within theadditional user-accounts region 654, indicating that the user-account Dis not currently enabled to subscribe to the playback queue 606. (Inother embodiments, a particular playback queue can be made publicallyavailable for any user-account to subscribe to.)

In this context, the method 500 may further include, prior toconfiguring the first playback device to enable the one or more otheruser-accounts to subscribe to the playback queue, receiving a command toenable the one or more other user-accounts to subscribe to the playbackqueue; and in response to receiving the command, configuring the firstplayback device to enable the one or more other user-accounts tosubscribe to the playback queue.

For example, prior to configuring the playback device 604 to enable theuser-account B to subscribe to the playback queue 606, the controldevice 602 may receive a command to enable the user-accounts B, C, and Dto subscribe to the playback queue 606. Such a command may take the formof a series of touch-and-drag inputs. For example, a touch input may bereceived at the subscriber indicator 644, and the subscriber indicator644 may be dragged from the additional user-accounts region 654 into thesubscriber region 652, as depicted at 660. The subscriber indicators 640and 642 may have similarly been dragged from the additionaluser-accounts region 654 into the subscriber region 652, therebyenabling the user-accounts B and C to subscribe to the playback queue606.

The method 500 may further include, prior to receiving the subscriptionindication, sending a message to the second playback device indicatingthat the second user-account is enabled to subscribe to the playbackqueue. For example, as shown in FIG. 6A, the control device 602 may sendmessage 670 to the playback device 608 (or a controller configured tocontrol playback device 608) indicating that the user-account B isenabled to subscribe to the playback queue 606.

The method 500 may further include, prior to receiving the subscriptionindication, causing the first playback device to inform the secondplayback device that the second user-account is enabled to subscribe tothe playback queue. For example, the control device 602 may send acommand 621 to the playback device 604 causing the playback device 604to send a message 672 to the playback device 608. The message 672 mayindicate that the user-account B is enabled to subscribe to the playbackqueue 606.

The method 500 may further include receiving an inactivity indicationthat the second user-account is subscribed to the playback queue but thesecond playback device is not currently playing an audio track from theplayback queue; and displaying a subscriber indicator on the controldevice showing that the second user-account has subscribed to theplayback queue but the second playback device is not currently playingan audio track from the playback queue.

As an example, the control device 602 may receive an indication 676 fromthe playback device 610 that the user-account C is subscribed to theplayback queue 606 but is not currently playing an audio track from theplayback queue 606. In response, the control device 602 may display thesubscriber indicator 642 that indicates that the user-account C issubscribed to the playback queue 606 but is not currently playing anaudio track from the playback queue 606. The subscriber indicator 642may so indicate by appearing in a second state as indicated by thedashed lines of subscriber indicator 642.

The method 500 may further include receiving data representing feedbackfrom the second user-account. The feedback may be associated with anaudio track of the playback queue. In this context, the method 500 mayfurther include displaying an indicator that represents the feedback.

For example, the control device 602 may receive feedback data 674 fromthe user-account D via the playback device 612 or perhaps a controldevice configured to control playback device 612. The feedback data 674may include textual or graphical information indicating user sentimentregarding an audio track of the playback queue 606. For example, thefeedback data may include information such as “I like this track” orvarious emoticons representing any positive, negative, or neutralsentiments. As an example, upon receiving the feedback data 674 thecontrol device 602 may display a subscriber indicator 644 indicatingthat a user associated with user-account D has positive feelings whilelistening to the audio track of the playback queue 606 being played bythe playback device 612.

The method 500 may further include receiving an input representing aselection of the subscriber indicator; and in response to receiving theinput, providing a user-interface for sending a message to the seconduser-account.

The method 500 may further include displaying an emoticon via theuser-interface; receiving, via the user-interface, an input representinga selection of the emoticon; and sending, to the second playback deviceor to a second control device configured to control the second playbackdevice, data representing the emoticon.

For example, a touchscreen of the control device 602 may receive touchinput at the subscriber indicator 640, and in response, the controldevice 602 may display messaging user-interface 680. As shown in FIG.6A, the messaging user-interface 680 provides nine emoticonsrepresenting various sentiments to be expressed to a user associatedwith the user-account B. By receiving touch input at a given emoticon ofthe messaging user-interface 680, the control device 602 may send amessage to the playback device 608 or a control device (not shown)configured to control the playback device 608. The message (not shown)may indicate the selected emoticon or include other data representingthe sentiment corresponding to the selected emoticon.

In other examples, the messaging user-interface 680 may be a touchscreenkeyboard for receiving input representing a textual message for the userassociated with user-account B. In such a case, the control device 602may send data representing the textual message to the playback device608 or a control device (not shown) configured to control the playbackdevice 608.

The method 500 may further include displaying a playback queue indicatorthat identifies the playback queue. For example, the control device 602may display the queue indicator 682. The queue indicator 682 indicatesthat the playback queue 606 corresponds to a “living room” playback zonecomprising the playback device 604 and possibly other playback devices.In some examples, the control device 602 may, in response to receivingappropriate control input, display subscriber indicator(s), globalindicator(s), and active account indicator(s) that provide informationpertaining to another playback queue that corresponds to anotherplayback zone or group of playback devices.

Referring to FIG. 7, the method 700 may be performed by a control deviceconfigured to control a first playback system. In some embodiments, thefirst playback system comprises a first group of one or more playbackdevices and a second group of one or more playback devices.

As an example, FIG. 8A depicts a control device 802 that is configuredto control a playback system 804. The playback system 804 is associatedwith user-account A and includes a group 806 of one or more playbackdevices and a group 808 of one or more playback devices. The group 806is configured to access the playback queue 810 for playback of audiocontent. FIG. 8 also includes playback system 812 which is associatedwith user-account B and playback system 814 which is associated withuser-account C. The playback system 814 is configured to access theplayback queue 816 for playback of audio content.

At block 702, the method 700 includes receiving a notification that asecond playback system associated with a second user-account isaccessing a first playback queue of the first group of playback devices.In this context, the first playback system and the control device may beassociated with a first user-account.

Referring to FIG. 8A for example, the control device 802 may receive anotification from the playback system 804 or from the playback system812. The notification may indicate that the playback system 812 isaccessing the playback queue 810. For example, the playback system 812may send the notification to the control device 802 as the playbacksystem 812 is accessing the playback queue 810. Alternatively, theplayback system 804 may detect that the playback system 812 is accessingthe playback queue 810 and send the notification to the control device802 in response.

At block 704, the method 700 includes displaying a first indication thatthe second playback system is accessing the first playback queue.

For instance, the control device 802 may display indication 818, whichshows that the playback system 812 is accessing the playback queue 810.The indication may explicitly identify the playback system 812, or asshown in FIG. 8A the indication 818 may identify user-account B which isassociated with the playback system 812. The indication 818 may indicatethat the group 806 is also accessing the playback queue 810.

At block 706, the method 700 includes receiving a command for the secondgroup of playback devices to access a second playback queue of a thirdplayback system. In this context, the third playback system may beassociated with a third user-account.

Referring to FIG. 8B for example, the control device 802 is shownoperating in a subscription management mode. The control device 802 isshown displaying an additional user-account region 854 and a playbackqueue region 852 within a touchscreen. A subscriber indicator 824 isdisplayed within the additional user-account region 854. The controldevice 802 receives a command, perhaps including a touch-and-drag input860 that moves the subscriber indicator 824 from the additionaluser-account region 854 to the playback queue region 852. The subscriberindicator 824 identifies user-account C which is associated with theplayback system 814. Therefore, the control device 802 may recognizethis touch-and-drag input 860 as a command for the group 808 to accessthe playback queue 816.

At block 708, the method 700 includes in response to receiving thecommand, configuring the second group of playback devices to access thesecond playback queue. For example, in response to the received command,the control device 802 may send a command to the playback system 804 forthe group 808 to access the playback queue 816. In response, the group808 may access the playback queue 816.

At block 710, the method 700 includes displaying a second indicationthat the second group of playback devices is accessing the secondplayback queue. For example the control device 802 may display theindication 820, which shows that the group 808 is accessing the playbackqueue 816. The indication 820 may explicitly identify the playbacksystem 814, or as shown in FIG. 8A the indication 820 may identifyuser-account C which is associated with the playback system 814.

The method 700 may further include, prior to receiving the notification,receiving a command to allow the second playback system to access thefirst playback queue; and sending a message indicating that the secondplayback system is allowed to access the first playback queue.

As shown in FIG. 8C for example, the control device 802 may receive atouch-and-drag input 870 that moves the subscriber indicator 826 fromthe additional user-account region 864 to the subscriber region 862. Thesubscriber indicator 826 identifies user-account B which is associatedwith the playback system 812. Therefore, the control device 802 mayrecognize touch-and-drag input 870 as a command to allow the playbacksystem 812 to access the playback queue 810. In response, the controldevice 802 may send a message indicating that the playback system 812 isallowed to access the playback queue 810. The message may be sent to theplayback system 804 and/or the playback system 812.

The method 700 may further include in response to receiving the command,sending a request for the second group of playback devices to access thesecond playback queue; receiving a message indicating that the secondgroup of playback devices is allowed to access the second playbackqueue; and causing the second group of playback devices to access thesecond playback queue.

For example, based on receiving the command for the group 808 to accessthe playback queue 816, the control device 802 may send, to the playbacksystem 804 a request for the group 808 to access the playback queue 816.Thereafter, either the playback system 804 or the playback system 814may send a message to the control device 802. The message may indicatethat the group 808 is allowed to access the playback queue 816. Inresponse to receiving the message, the control device 802 may cause thegroup 808 to access the playback queue 816. For example, the controldevice 802 may send to the playback system 804 a command for the group808 to access the playback queue 816.

The method 700 may further include receiving a second notification thatthe second playback system is no longer accessing the first playbackqueue; and displaying an indication that the second playback system isallowed to access the first playback queue but is no longer accessingthe first playback queue.

For example, the control device 802 may receive a second notificationthat the playback system 812 is no longer accessing the playback queue810, and in response display the subscriber indicator 826 in a secondstate that indicates that the playback system 812 is no longer accessingthe playback queue 810. The subscriber indicator 826 may appear in thesecond state similarly to the subscriber indicator 642 of FIG. 6A (e.g.,dashed lines, greyed out, etc.).

The method 700 may further include receiving data representing feedbackfrom the second user-account, wherein the feedback is associated withthe first playback queue; and displaying an indication of the feedback.For example, the control device 802 may receive, from the playbacksystem 812, data representing feedback from the user-account B regardingmedia content of the playback queue 810. In response, the control device802 may display the subscriber indicator 826 in a third state that isindicative of the feedback from the user-account B. For example, thesubscriber indicator 826 may appear in a third state similar to that ofsubscriber indicator 644 of FIG. 6A. More specifically, the subscriberindicator 826 may appear in a form which indicates that the userassociated with user-account B is pleased, displeased, or ambivalent,with the media content of playback queue 810 played by the playbacksystem 812. The subscriber indicator 826 appearing in the third statemay identify other sentiments of the user associated with user-account Bas well.

Referring to FIG. 9, the method 900 may be performed by a control deviceconfigured to control a first playback system. The first playback systemmay comprise a first group of one or more playback devices and a secondgroup of one or more playback devices.

As an example, FIG. 10 depicts a control device 1002 that is configuredto control a playback system 1004. The playback system 1004 isassociated with user-account A and includes a group 1006 of one or moreplayback devices and a group 1008 of one or more playback devices. Thegroup 1006 is configured to access the playback queue 1010 for playbackof audio content and the group 1008 is configured to access the playbackqueue 1012 for playback of audio content. FIG. 10 also includes playbacksystem 1014 which is associated with user-account B and playback system1016 which is associated with user-account C.

At block 902, the method 900 includes receiving a first notificationthat a second playback system associated with a second user-account isaccessing a first playback queue of the first group of playback devices.In this context, the first playback system and the control device areassociated with a first user-account.

For example, the control device 1002 may receive a first notificationfrom the playback system 1014 or the playback system 1004. The firstnotification may indicate that the playback system 1014 is accessing theplayback queue 1010. For example, the playback system 1014 may send thefirst notification as the playback system 1014 is accessing the playbackqueue 1010. Alternatively, the playback system 1004 may detect that theplayback system 1014 is accessing the playback queue 1010 and send thefirst notification to the control device 1002 in response.

At block 904, the method 900 includes displaying a first indication thatthe second playback system is accessing the first playback queue.

For instance, the control device 1002 may display indication 1018, whichindicates that the playback system 1014 is accessing the playback queue1010. The indication may explicitly identify the playback system 1014,or as shown in FIG. 10 the indication 1018 may identify user-account Bwhich is associated with the playback system 1014. The indication 1018may indicate that the group 1006 is also accessing the playback queue1010.

At block 906, the method 900 includes receiving a second notificationthat a third playback system associated with a third user-account isaccessing a second playback queue of the second group of playbackdevices.

For instance, the control device 1002 may receive a second notificationfrom the playback system 1004 or the playback system 1016 indicatingthat the playback system 1016 is accessing the playback queue 1012. Forexample, the playback system 1016 may send the second notification asthe playback system 1016 is accessing the playback queue 1012.Alternatively, the playback system 1004 may detect that the playbacksystem 1016 is accessing the playback queue 1012 and send the secondnotification to the control device 1002 in response.

At block 908, the method 900 includes displaying a second indicationthat the third playback system is accessing the second playback queue.

For instance, the control device 1002 may display indication 1020, whichindicates that the playback system 1016 is accessing the playback queue1012. The indication may explicitly identify the playback system 1016,or as shown in FIG. 10 the indication 1020 may identify user-account Cwhich is associated with the playback system 1016. The indication 1020may indicate that the group 1008 is also accessing the playback queue1012.

The method 900 may further include prior to receiving the firstnotification, receiving a command to allow the second playback system toaccess the first playback queue; and sending a message indicating thatthe second playback system is allowed to access the first playbackqueue.

For example, the control device 1002 may, prior to receiving the firstnotification, receive a command to allow the playback system 1014 toaccess the playback queue 1010. The control device 1002 may receive thecommand in a manner similar to functions of the control device 802described above with reference to FIG. 8C. After receiving the command,the control device 1002 may send to the playback system 1004 and/or theplayback system 1014 a message indicating that the playback system 1014is allowed to access the playback queue 1010.

The method 900 may further include receiving a second notification thatthe second playback system is no longer accessing the first playbackqueue; and displaying an indication that the second playback system isallowed to access the first playback queue but is no longer accessingthe first playback queue.

For example, the control device 1002 may receive an indication that theplayback system 1014 is no longer accessing the playback queue 1010, andin response display the subscriber indicator 1024 in a second state thatindicates that the playback system 1014 is no longer accessing theplayback queue 1010. The subscriber indicator 1024 may appear in thesecond state similarly to the subscriber indicator 642 of FIG. 6A (e.g.,dashed lines, greyed out, etc.).

Referring to FIGS. 11A and 11B, the method 1100 may be performed by acontrol device configured to control a first playback system. The firstplayback system may comprise a first group of one or more playbackdevices and a second group of one or more playback devices.

As an example, FIG. 12 depicts a control device 1202 that is configuredto control a playback system 1204. The playback system 1204 isassociated with user-account A and includes a group 1206 of one or moreplayback devices and a group 1208 of one or more playback devices. FIG.12 also includes playback system 1210 which is associated withuser-account B and playback system 1212 which is associated withuser-account C. The playback system 1210 is configured to accessplayback queue 1214 for playback of audio content and the playbacksystem 1212 is configured to access playback queue 1216 for playback ofaudio content.

At block 1102, the method 1100 includes receiving a first command forthe first group of playback devices to access a first playback queue ofa second playback system. The second playback system is associated witha second user-account.

For example, the control device 1202 may receive a command for the group1206 to access the playback queue 1214. The command may be received in amanner similar to that depicted in FIG. 8B and related descriptionabove.

At block 1104, the method 1100 includes, based on receiving the firstcommand, causing the first group of playback devices to access the firstplayback queue. For example, the control device 1202 may send a commandto the playback system 1204 for the group 1206 to access the playbackqueue 1214. In response to the command, the group 1206 may access theplayback queue 1214.

At block 1106, the method 1100 includes displaying a first indicationthat the first group of playback devices is accessing the first playbackqueue. For example the control device 1202 may display the indication1218, which indicates that the group 1206 is accessing the playbackqueue 1214. The indication 1218 may explicitly identify the playbacksystem 1210, or as shown in FIG. 12 the indication 1218 may identifyuser-account B which is associated with the playback system 1210.

At block 1108, the method 1100 includes receiving a second command forthe second group of playback devices to access a second playback queueof a third playback system. In this context, the third playback systemis associated with a third user-account.

For example, the control device 1202 may receive a command for the group1208 to access the playback queue 1216. The command may be received in amanner similar to that depicted in FIG. 8B and related descriptionabove.

At block 1110, the method 1100 includes, based on receiving the secondcommand, causing the second group of playback devices to access thesecond playback queue. For example, the control device 1202 may send acommand to the playback system 1204 for the group 1208 to access theplayback queue 1216. In response to the command, the group 1208 mayaccess the playback queue 1216.

At block 1112, the method 1100 includes displaying a second indicationthat the second group of playback devices is accessing the secondplayback queue. For example the control device 1202 may display theindication 1220, which indicates that the group 1208 is accessing theplayback queue 1216. The indication 1220 may explicitly identify theplayback system 1212, or as shown in FIG. 12 the indication 1220 mayidentify user-account C which is associated with the playback system1212.

IV. Conclusion

The description above discloses, among other things, various examplesystems, methods, apparatus, and articles of manufacture including,among other components, firmware and/or software executed on hardware.It is understood that such examples are merely illustrative and shouldnot be considered as limiting. For example, it is contemplated that anyor all of the firmware, hardware, and/or software aspects or componentscan be embodied exclusively in hardware, exclusively in software,exclusively in firmware, or in any combination of hardware, software,and/or firmware. Accordingly, the examples provided are not the onlyway(s) to implement such systems, methods, apparatus, and/or articles ofmanufacture.

Examples described herein involve, among other things, a control deviceconfiguring a first playback device associated with a first user-accountto (i) play media content from a playback queue comprising one or moreaudio tracks stored at a network location and (ii) enable one or moreother user-accounts associated with other playback devices to subscribeto the playback queue; the control device receiving a subscriptionindication that a second user-account associated with a second playbackdevice has subscribed to the playback queue; and in response toreceiving the subscription indication, the control device displaying asubscriber indicator showing that the second user-account has subscribedto the playback queue. Other aspects of the examples will be madeapparent in the remainder of the description herein.

Additionally, references herein to “embodiment” means that a particularfeature, structure, or characteristic described in connection with theembodiment can be included in at least one example embodiment of aninvention. The appearances of this phrase in various places in thespecification are not necessarily all referring to the same embodiment,nor are separate or alternative embodiments mutually exclusive of otherembodiments. As such, the embodiments described herein, explicitly andimplicitly understood by one skilled in the art, can be combined withother embodiments.

The specification is presented largely in terms of illustrativeenvironments, systems, procedures, steps, logic blocks, processing, andother symbolic representations that directly or indirectly resemble theoperations of data processing devices coupled to networks. These processdescriptions and representations are typically used by those skilled inthe art to most effectively convey the substance of their work to othersskilled in the art. Numerous specific details are set forth to provide athorough understanding of the present disclosure. However, it isunderstood to those skilled in the art that certain embodiments of thepresent disclosure can be practiced without certain, specific details.In other instances, well known methods, procedures, components, andcircuitry have not been described in detail to avoid unnecessarilyobscuring aspects of the embodiments. Accordingly, the scope of thepresent disclosure is defined by the appended claims rather than theforgoing description of embodiments.

When any of the appended claims are read to cover a purely softwareand/or firmware implementation, at least one of the elements in at leastone example is hereby expressly defined to include a tangible,non-transitory medium such as a memory, DVD, CD, Blu-ray, and so on,storing the software and/or firmware.

We claim:
 1. A method to be performed by one or more servers of acomputing system, the method comprising: receiving, via a networkinterface from a first computing device, an instruction to enablesubscription to a first playback queue associated with a first mediaplayback system, wherein the first media playback system comprises afirst playback device, and wherein one or more first accounts areregistered with the first media playback system; in response to theinstruction, enabling one or more second user accounts to subscribe tothe first playback queue via one or more wide area networks, wherein theone or more second user accounts are registered with respective secondmedia playback systems in respective second households; after enablingthe one or more second user accounts associated with one or more secondplayback devices to subscribe to the first playback queue, receiving,via the network interface from a particular second media playbacksystem, a request to subscribe to the first playback queue; and inresponse to the request to subscribe to the first playback queue: (i)sending, via the network interface, one or more messages that update acontrol interface of the first control device to display a subscriberindication showing that a particular second user account registered withthe particular second media playback system has subscribed to the firstplayback queue and (ii) sending, via the network interface, one or moremessages that populate a second playback queue associated with a secondplayback device of the particular second media playback system withaudio tracks of the first playback queue.
 2. The method of claim 1,further comprising: while the first playback device is playing back aparticular audio track of the first playback queue, receiving a firstdata stream with timing information corresponding to the playback of theparticular audio track by the first playback device; and sending, to theparticular second media playback system, a second data stream with thetiming information corresponding to the playback of the particular audiotrack by the first playback device, wherein the second playback deviceplays the particular audio track according to the timing information atthe substantially same time as the first playback device.
 3. The methodof claim 1, further comprising: hosting the first playback queue, andwherein the first playback queue identifies respective network locationsof the audio tracks indicated within the first playback queue, andwherein the first playback device streams the audio tracks indicatedwithin the first playback queue from the respective network locationsduring playback.
 4. The method of claim 3, further comprising: hostingthe second playback queue, wherein the second playback device streamsthe audio tracks indicated within the second playback queue from therespective network locations during playback.
 5. The method of claim 1,further comprising: receiving, via the network interface, statusinformation indicating whether the particular second media playbacksystem is currently playing back the first playback queue, when theparticular second media playback system is currently playing back thefirst playback queue, sending one or more instructions to update thecontrol interface of the first control device to display a graphicalindication that the particular second user account is playing back thefirst playback queue; and when the particular second media playbacksystem is not currently playing back the first playback queue, sendingone or more instructions to update the control interface of the firstcontrol device to display the subscriber indication showing that theparticular second user account has subscribed to the first playbackqueue.
 6. The method of claim 1, further comprising: receiving, from thefirst media playback system, one or more message indicating that thefirst playback device is playing back the first playback queue; andsending, via the network interface, an invitation for the particularsecond media playback system to start playing back the first playbackqueue with the first playback device.
 7. The method of claim 1, whereina network location of a first audio track indicated within the firstplayback queue is at one or more servers of a first streaming audioservice, and wherein a network location of a second audio trackindicated within the first playback queue is at one or more servers of asecond streaming audio service.
 8. A computing system comprising: anetwork interface; one or more processors; data storage having storedtherein instructions executable by the one or more processors to causethe computing system to perform a method comprising receiving, via anetwork interface from a first computing device, an instruction toenable subscription to a first playback queue associated with a firstmedia playback system, wherein the first media playback system comprisesa first playback device, and wherein one or more first accounts areregistered with the first media playback system; in response to theinstruction, enabling one or more second user accounts to subscribe tothe first playback queue via one or more wide area networks, wherein theone or more second user accounts are registered with respective secondmedia playback systems in respective second households; after enablingthe one or more second user accounts associated with one or more secondplayback devices to subscribe to the first playback queue, receiving,via the network interface from a particular second media playbacksystem, a request to subscribe to the first playback queue; and inresponse to the request to subscribe to the first playback queue: (i)sending, via the network interface, one or more messages that update acontrol interface of the first control device to display a subscriberindication showing that a particular second user account registered withthe particular second media playback system has subscribed to the firstplayback queue and (ii) sending, via the network interface, one or moremessages that populate a second playback queue associated with a secondplayback device of the particular second media playback system withaudio tracks of the first playback queue.
 9. The computing system ofclaim 8, wherein the method further comprises: while the first playbackdevice is playing back a particular audio track of the first playbackqueue, receiving a first data stream with timing informationcorresponding to the playback of the particular audio track by the firstplayback device; and sending, to the particular second media playbacksystem, a second data stream with the timing information correspondingto the playback of the particular audio track by the first playbackdevice, wherein the second playback device plays the particular audiotrack according to the timing information at the substantially same timeas the first playback device.
 10. The computing system of claim 8,wherein the method further comprises: hosting the first playback queue,and wherein the first playback queue identifies respective networklocations of the audio tracks indicated within the first playback queue,and wherein the first playback device streams the audio tracks indicatedwithin the first playback queue from the respective network locationsduring playback.
 11. The computing system of claim 8, wherein the methodfurther comprises: hosting the second playback queue, wherein the secondplayback device streams the audio tracks indicated within the secondplayback queue from the respective network locations during playback.12. The computing system of claim 8, wherein the method furthercomprises: receiving, via the network interface, status informationindicating whether the particular second media playback system iscurrently playing back the first playback queue, when the particularsecond media playback system is currently playing back the firstplayback queue, sending one or more instructions to update the controlinterface of the first control device to display a graphical indicationthat the particular second user account is playing back the firstplayback queue; and when the particular second media playback system isnot currently playing back the first playback queue, sending one or moreinstructions to update the control interface of the first control deviceto display the subscriber indication showing that the particular seconduser account has subscribed to the first playback queue.
 13. Thecomputing system of claim 8, wherein the method further comprises:receiving, from the first media playback system, one or more messageindicating that the first playback device is playing back the firstplayback queue; and sending, via the network interface, an invitationfor the particular second media playback system to start playing backthe first playback queue with the first playback device.
 14. Thecomputing system of claim 8, wherein a network location of a first audiotrack indicated within the first playback queue is at one or moreservers of a first streaming audio service, and wherein a networklocation of a second audio track indicated within the first playbackqueue is at one or more servers of a second streaming audio service. 15.A non-transitory, computer-readable medium having instructions storedthereon that, when executed by one or more processors cause a computingsystem to perform a method comprising: receiving, via a networkinterface from a first computing device, an instruction to enablesubscription to a first playback queue associated with a first mediaplayback system, wherein the first media playback system comprises afirst playback device, and wherein one or more first accounts areregistered with the first media playback system; in response to theinstruction, enabling one or more second user accounts to subscribe tothe first playback queue via one or more wide area networks, wherein theone or more second user accounts are registered with respective secondmedia playback systems in respective second households; after enablingthe one or more second user accounts associated with one or more secondplayback devices to subscribe to the first playback queue, receiving,via the network interface from a particular second media playbacksystem, a request to subscribe to the first playback queue; and inresponse to the request to subscribe to the first playback queue: (i)sending, via the network interface, one or more messages that update acontrol interface of the first control device to display a subscriberindication showing that a particular second user account registered withthe particular second media playback system has subscribed to the firstplayback queue and (ii) sending, via the network interface, one or moremessages that populate a second playback queue associated with a secondplayback device of the particular second media playback system withaudio tracks of the first playback queue.
 16. The non-transitory,computer-readable medium of claim 15, wherein the method furthercomprises: while the first playback device is playing back a particularaudio track of the first playback queue, receiving a first data streamwith timing information corresponding to the playback of the particularaudio track by the first playback device; and sending, to the particularsecond media playback system, a second data stream with the timinginformation corresponding to the playback of the particular audio trackby the first playback device, wherein the second playback device playsthe particular audio track according to the timing information at thesubstantially same time as the first playback device.
 17. Thenon-transitory, computer-readable medium of claim 15, wherein the methodfurther comprises: hosting the first playback queue, and wherein thefirst playback queue identifies respective network locations of theaudio tracks indicated within the first playback queue, and wherein thefirst playback device streams the audio tracks indicated within thefirst playback queue from the respective network locations duringplayback.
 18. The non-transitory, computer-readable medium of claim 15,wherein the method further comprises: hosting the second playback queue,wherein the second playback device streams the audio tracks indicatedwithin the second playback queue from the respective network locationsduring playback.
 19. The non-transitory, computer-readable medium ofclaim 15, wherein the method further comprises: receiving, via thenetwork interface, status information indicating whether the particularsecond media playback system is currently playing back the firstplayback queue, when the particular second media playback system iscurrently playing back the first playback queue, sending one or moreinstructions to update the control interface of the first control deviceto display a graphical indication that the particular second useraccount is playing back the first playback queue; and when theparticular second media playback system is not currently playing backthe first playback queue, sending one or more instructions to update thecontrol interface of the first control device to display the subscriberindication showing that the particular second user account hassubscribed to the first playback queue.
 20. The non-transitory,computer-readable medium of claim 15, wherein the method furthercomprises: receiving, from the first media playback system, one or moremessage indicating that the first playback device is playing back thefirst playback queue; and sending, via the network interface, aninvitation for the particular second media playback system to startplaying back the first playback queue with the first playback device.